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The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

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<h4><a name = "tag_001_014_2201">&nbsp;</a>NAME</h4><blockquote>
talk - talk to another user
</blockquote><h4><a name = "tag_001_014_2202">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

talk <i>address </i><b>[</b><i>terminal</i><b>]</b>
</code>
</pre>
</blockquote><h4><a name = "tag_001_014_2203">&nbsp;</a>DESCRIPTION</h4><blockquote>
The
<i>talk</i>
utility is a two-way, screen-oriented communication program.
<p>
When first invoked,
<i>talk</i>
sends a message similar to:
<pre>
<code>
Message from <i>&lt;unspecified string&gt;</i>
talk: connection requested by <i>your_address</i>
talk: respond with: talk <i>your_address</i>
</code>
</pre>
to the specified
<i>address</i>.
At this point, the recipient
of the message can reply by typing:
<pre>
<code>
talk &nbsp;<i>your_address
</i></code>
</pre>
<p>
Once communication is established, the two parties can type
simultaneously, with their output
displayed in separate regions
of the screen.
Characters are processed as follows:
<ul>
<p>
<li>
Typing the
alert
character will alert
the recipient's terminal.
<p>
<li>
Typing
&lt;control&gt;-L
will cause the sender's
screen regions to be refreshed.
<p>
<li>
Typing the erase and kill
characters will affect the sender's terminal
in the manner described by the
<b>termios</b>
interface in
the <b>XBD</b> specification, <a href="../xbd/termios.html"><b>General Terminal Interface</b>&nbsp;</a> .
<p>
<li>
Typing the interrupt or end-of-file characters will terminate the local
<i>talk</i>
utility.
Once the
<i>talk</i>
session has been terminated on one side, the other
side of the
<i>talk</i>
session will be notified that the
<i>talk</i>
session has been terminated and will be able to do nothing except exit.
<p>
<li>
Typing characters from LC_CTYPE classifications
<b>print</b>
or
<b>space</b>
will cause those characters to be sent to the recipient's terminal.
<p>
<li>
When and only when the
<i><a href="stty.html">stty</a></i>
<i>iexten</i>
local mode
is enabled,
the existence and processing of
additional special control
characters and
multi-byte or single-byte functions is implementation-dependent.
<p>
<li>
Typing other non-printable characters
will cause implementation-dependent sequences of
printable characters to be sent to the recipient's terminal.
<p>
</ul>
<p>
Permission to
be a recipient of a
<i>talk</i>
message can be denied or granted by use of the
<i><a href="mesg.html">mesg</a></i>
utility.
However, a user's privilege may further constrain
the domain of accessibility of other users' terminals.
The
<i>talk</i>
utility
will fail when the user lacks the appropriate privileges
to perform the requested action.
<p>
Certain block-mode terminals do not have all the capabilities necessary
to support the simultaneous exchange of messages required for
<i>talk</i>.
When this type of exchange cannot be supported on such terminals, the
implementation may support an exchange with reduced levels of
simultaneous interaction or it may report an error describing the
terminal-related deficiency.
</blockquote><h4><a name = "tag_001_014_2204">&nbsp;</a>OPTIONS</h4><blockquote>
None.
</blockquote><h4><a name = "tag_001_014_2205">&nbsp;</a>OPERANDS</h4><blockquote>
The following operands are supported:
<dl compact>

<dt><i>address</i><dd>The recipient of the
<i>talk</i>
session.
One form of
<i>address</i>
is the
&lt;<i>user&nbsp;name</i>&gt;,
as returned by the
<i><a href="who.html">who</a></i>
utility.
Other address formats and how they are handled are unspecified.

<dt><i>terminal</i><dd>
If the recipient is logged in more than once, the
<i>terminal</i>
argument can be used to indicate the appropriate terminal name.
If
<i>terminal</i>
is not specified, the
<i>talk</i>
message will be displayed on one or more accessible terminals
in use by the recipient.
The format of
<i>terminal</i>
will be the same as that returned by the
<i><a href="who.html">who</a></i>
utility.

</dl>
</blockquote><h4><a name = "tag_001_014_2206">&nbsp;</a>STDIN</h4><blockquote>
Characters read from standard input will be copied to the
recipient's terminal in an unspecified manner.
If standard input is not a terminal, talk will write a diagnostic
message and exit with a non-zero status.
</blockquote><h4><a name = "tag_001_014_2207">&nbsp;</a>INPUT FILES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_001_014_2208">&nbsp;</a>ENVIRONMENT VARIABLES</h4><blockquote>
The following environment variables affect the execution of
<i>talk</i>:
<dl compact>

<dt><i>LANG</i><dd>Provide a default value for the internationalisation variables
that are unset or null.
If
<i>LANG</i>
is unset or null, the corresponding value from the
implementation-dependent default locale will be used.
If any of the internationalisation variables contains an invalid setting, the
utility will behave as if none of the variables had been defined.

<dt><i>LC_ALL</i><dd>
If set to a non-empty string value,
override the values of all the other internationalisation variables.

<dt><i>LC_CTYPE</i><dd>
Determine the
locale for the interpretation of sequences of bytes of text data as
characters (for example, single- as opposed to multi-byte characters
in arguments and input files).
If the recipient's locale does not use an LC_CTYPE equivalent
to the sender's, the results are undefined.

<dt><i>LC_MESSAGES</i><dd>
Determine the locale that should be used to affect
the format and contents of diagnostic
messages written to standard error
and informative messages written to standard output.

<dt><i>NLSPATH</i><dd>
Determine the location of message catalogues
for the processing of
<i>LC_MESSAGES .
</i>
<dt><i>TERM</i><dd>Determine
the name of the invoker's terminal type.
If this variable is
unset or null, an unspecified default terminal type will be used.

</dl>
</blockquote><h4><a name = "tag_001_014_2209">&nbsp;</a>ASYNCHRONOUS EVENTS</h4><blockquote>
When the
<i>talk</i>
utility receives a SIGINT signal,
the utility will terminate and exit with a zero status.
It will take the standard action for all other signals.
</blockquote><h4><a name = "tag_001_014_2210">&nbsp;</a>STDOUT</h4><blockquote>
If standard output is a terminal,
characters copied from the recipient's standard input
may be written to standard output.
Standard output also may be used for diagnostic messages.
If standard output is not a terminal,
<i>talk</i>
will exit with a non-zero status.
</blockquote><h4><a name = "tag_001_014_2211">&nbsp;</a>STDERR</h4><blockquote>
None.
</blockquote><h4><a name = "tag_001_014_2212">&nbsp;</a>OUTPUT FILES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_001_014_2213">&nbsp;</a>EXTENDED DESCRIPTION</h4><blockquote>
None.
</blockquote><h4><a name = "tag_001_014_2214">&nbsp;</a>EXIT STATUS</h4><blockquote>
The following exit values are returned:
<dl compact>

<dt>0<dd>Successful completion.

<dt>&gt;0<dd>An error occurred or
<i>talk</i>
was invoked on a terminal incapable of supporting it.

</dl>
</blockquote><h4><a name = "tag_001_014_2215">&nbsp;</a>CONSEQUENCES OF ERRORS</h4><blockquote>
Default.
</blockquote><h4><a name = "tag_001_014_2216">&nbsp;</a>APPLICATION USAGE</h4><blockquote>
Because the handling of non-printable, non-space characters
is tied to the
<i><a href="stty.html">stty</a></i>
description of
<i>iexten</i>,
implementation extensions within the terminal driver
can be accessed.
For example, some implementations provide line editing
functions with certain control character sequences.
</blockquote><h4><a name = "tag_001_014_2217">&nbsp;</a>EXAMPLES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_001_014_2218">&nbsp;</a>FUTURE DIRECTIONS</h4><blockquote>
None.
</blockquote><h4><a name = "tag_001_014_2219">&nbsp;</a>SEE ALSO</h4><blockquote>
<i><a href="mesg.html">mesg</a></i>,
<i><a href="who.html">who</a></i>,
<i><a href="write.html">write</a></i>,
the <b>XBD</b> specification, <a href="../xbd/termios.html"><b>General Terminal Interface</b>&nbsp;</a> .
</blockquote><hr size=2 noshade>
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Copyright &copy; 1997 The Open Group
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